Rotary engine



April 7, 1931. s. PLATO 1,799,527

ROTARY' ENGINE Filed Nov; 8, '1928 2 Sheets-Sheet l INVEA/TU/E GE'RHARDTPLATO ATwE/VEY April 7,1931.

2 Sheds-Sheet ,2

GE/PHARDT PLATO BYM w Patented Apr. 7, I 1931 PATENT OFFIC GERHARDTPLATO, OI CHICAGO, ILLINOIS sonar meme Application filed li'ovember a,1928. Serial No. 317,889.

My invention relates to an improved con struction of rotary engine ofthe multi-cylinder type by which special provision is made for coolingeach cylinder of the engine by a freshair charge, during, each cycle ofits operation to prevent excessive heating, and by which a plurality ofcharges of mixture may be compressed in a mixture chamber for each cycleof operation of each cylinder. 7 p 13 Y The above and other objects ofmy invention will best be understood b the accompanying drawings s owinga preferred embodiment thereof, in which Fig. 1 is a vertical sectionalview taken transversely through one cylinder of my engine, this viewbeing ta en along the line 11 in Fig. 2, and

Fig. 2 is a view showing one cylinder of my engine in plan view, asecond cylinder in 2:) horizontal sectional view taken along the line2-2 in Fig. 1 and a third cylinder in horizontal sectional view takenalong the line 2a-2a in Fig. 1. e r V Similar numerals refer to similarparts throughout the several views.

As shown in Fig. 2, three cylinders are illustrated which are designated1, 2 and 3, which are of the same construction as far as the workingparts pertaining to each cylinder are concerned, from which it will benecessary to describe theworking parts of but one cylinder, for examplecylinder 1. Cylinder 2 is shown as broken in' a plane extendingtransversely of the cylinder to indicate the inclusion in the engine ofas many cylinders of the construction of cylinder 2 as desired, since Icontemplate providing my improved engine with as many cylinders as therequirements of any particular case may dictate.

As shown in Fi 1, cylinder 1 is provide with a cylindrical ore throughwhich a main shaft 10 extends co-axially .with the bore. The shaft 10 iscontinuous from end to end of the engine, and all ofthe cylindersemployed are arranged coaxially with the said shaft. Cylinder 1 isprovided with parallel end walls 11 and 12, the wall 12 alsoconstituting one of the end walls of cylinder 2. Between the walls 11and 12, the shaft 10 carries a piston 13, of a length fitting betweenthe end walls reference to.

d bore through a port 27.

with a sliding fit, to rotate in the cylinder 1. The piston 13 carriespacking bars 14 which are in sliding engagement with the bore of thecylinder at all times. The piston is rigidly secured to the shaft 10 bya key 15;

The piston 13 extends radially in one direction from the shaft 10 to aposition adjacent the bore of the cylinder, to carry the packing bars14, and said piston occupies but a small part of the volume of thecylinder, my to permit the action upon and by it, below described.

The block of the cylinder is extended upwardly above its bore andcontains a firing chamber 17 extending through the block andcommunicating with the cylinder bore by a port 18. The cylinder blockalso contains two passageways 19 provided at their lower ends with checkvalves 20 for receiving fuel mixture under pressure from the cylinderbore, through the ports 21 opening from the lower endsof the passagewaysinto the cylinderbore. Between the passa eways 19 and the firing chamber17, the cy inder block is provided with a curved slot 22 in which asimilarly curved gate or plate 23 is a sliding fit, said gate being ofsuch a-width that it is also a sliding fit at its edges between the endwalls 11 and 12 of the cylinder. The gate 23 always occupies the lowestposition made posan sible by the angular position of the piston 13 atany instant, and thus separates the bore of the cylinder into twocompartments, one in communication with the port 18 and the other incommunication with the ports 21.

The cylinder block also contains a bore 24 in which a housing 25 ismounted, which housin carries and guides an exhaust valve 26 havingcommunication with the cylinder The other side of no the exhaust valvecommunicates with an exhaust manifold 28.

The firing chamber 17 has extendin through its side wall, a spark plug29, an this side wall is also provided with an aper- 95 ture 30 in whicha check valve 31 is mounted, this valve being held in place by a cap 32closing the outer end of the aperture 30. A clear ance space 33 is leftbetween the cap 32 and the check valve 31 and with. this space, an air10.

supply pipe 34 communicates, which pipe is open at its outer end toatmosphere. The pigs 34 has extending into it a small diameter tu 35provided with a stop-cock 36 by which lubricating oil may bepermitted'to flow into the pipe 34 as rapidly as desired.

T e cylinder of the engine are provided with a head 37, preferablyextending over all of them, which serves for each cylinder to enclosethe firing chamber 17 and the passages 19,. and also the bore 24 at itsupper end, and it also provides an upper guide for the stem 26a of theexhaust valve. The head 37 also carries rods 38 holding the check valves20 in the lower ends of the passages 19.

As indicated in Fig. 2, the head 37 also carries two valves 39 and 40opening into each firing chamber 17, these valves having stems 39a and40a extending upwardly for operation by the valve operating mechanism.In

the head 37, each intake valve 40 opens into a passageway 41communicating with an intake manifold 42 for supplying the engine withfuel mixture from a carburetor not shown. The passageway 41 preferablyextends-throu hout the head 37 and communicates with a l of the intakevalves 40 for supplying the several cylinder initially with fuel vmixture from the manifold 42, which preferably communicates with thepassageway 41 at several points to distribute the mixture to thepassageway with the greatest eiiiciency. The passageways 19 communicateat their upper ends with a storage compartment 43 ormed in the ,head toreceive fuel mixture under compression from the several cylinders andthe compressed mixture valves 39, one for each cylinder,establishcommunication between said compartment 43 and the severalfiring chambers 17 when they are opened.-

The valve stems 26a, 39a and 40a extend above the upper surface of thehead 37 and are grovided with suitable springs as indicate for keegingthe valves closed unless they are opene by the valve operatingmechanlsm.

The head 37 supports in suitablebearings extending from its uppersurface, a cam shaft 44 for operating rocker arms 45, 46 and 47,engaging the upper ends respectively of the valve stems 26a, 39a and40a, to open the cor responding valveswhen the rocker arms are operated.The rocker arms are su )ported by shafts 48 and 49 carried by suitablebearin s extending upwardly from. the top of tfie head 37.

The cam construction and arrangement carried by the cam shaft 44, whichshaft preferably extends the entire length of the engine to operate allof the cam operated valves thereof, is determined by the number of c linders used in the engine construction an the particular t pe of cycledesired. In the three cylinder arrangement, which is shown in theaccompanying drawings as illustrative of one particular number ofcylinders that may be employed, I find it desirable to complete theentire cycle of operation of the engine in three rotations of the shaft10, and since the cam shaft 44 should make one rotation for eachcomplete cycle of operation of the engine, I show the shaft 44 asconnected with the shaft 10 by gears 50, 51 and 52, drivin the shaft 44from the shaft 10 at one-thir the speed of the shaft 10. The ears 50 and52 are rigidly secured to the sha ts 10 and 44, and the gear 51 is anidler gear supported on a stud 53 from one end wall of the engine.

The'cylinders of the engine may be provided with water 'ackets asindicated at 54 for cylinder 1 and each of the curved slots 22preferably connects at its upper end with a passageway 55 formed in thehead 37, which in turn communicates with the corres onding firingchamber 17.

n operating rotary engines of the type under consideration in the past,I have found that for high speeds, the heating effect is so great as tomake it difiicult to cool the engine and cause it to operate smoothly.To overcome this difficulty, I referably employ a cycle of operation incuding one or more cooling strokes or rotations in the following manner.Assuming that the engine is in operation, for the position of the partsshown in Fig. 1, and that afiring stroke has just been completed, endingthe preceding cycle of operation, continued rotation of the piston 13draws into the chamber 17 and through the port 18 in to the cylinderbore back of the piston 13, a charge of fuel mixture from thecarburetor, through the intake manifold 42, the intake valve 40 at thistime being held in its open position by a corresponding cam on the camshaft 44. I The check valve 31 is held against its seat by a spring ofsuflicient strength to hold it closed for suction pressures no greaterthan are required to draw into the engine charges of mixture from thecarbureter, and the check valve 31 therefore remains closed during theintake of fuel mixture for the stroke of the piston 13 underconsideration. At the same time, the exhaust valve 26 is held in itsopen position by a corresponding cam on the camshaft 44, and the burntgases resulting from the firing stroke previously com leted, are swe tfrom the cylinder through the port 27 an around the exhaust valve 26,into the exhaust manifold 28. The check valves 20 are held against theirseats b suitable springs having sufficient strengt1 to hold these valvesclosed for an pressures there may be upon gases in the cy inder bore,that are being swept by the piston from the cvlin'der bore throug theport 27 into the exhaust manifold 28, and in this way flow of the burntgases into the passageways 19 is prevented. The weight of the gate 23 atthis time holds it against the rear surface of the piston 13 andprevents in- 26 is opened by its cam,

termingling of the fuel mixture being drawn into the cylinder, and theburnt gases being expelled from it. When the first stroke or rotation ofthe piston 13 has progressed far enough -to bring the packing bars 14opposite the port 27, the exhaust valve 26 is permitted to close by thecam controlling it and the intake of fresh fuel mixture is continueduntil the packing bars 14 reach the port 18. At this time, the camcontrolling the valve 40 permits it to close, and when the packing bars14 pass the port 18 to begin the second stroke or. rotation of thepiston 13 of the particular cycle under consideration, the charge offresh mixture is contained in the cylinder in front of the piston 13 andis prevented from passing back through the port 18 by the gate 23.During the second stroke of the piston 13, the intake valve 40 and theexhaust valve 26 remain closed, and the mixture compressed by rotationof the piston 13 in the cylinder 1, is forced through the check valves20 into the passageways 19, and thus into the mixture chamber 43, whereit is held for a brief interval under compression sufficient to cause itto operate efficiently when it is subsequently delivered to the firingchamber 17 and ignited. During the second stroke of the piston 13, thevalve 39 is also in its closed position, as it also was during theentire first stroke of the piston 13 of the cycle under consideration,the strength of the spring of the valve 39, being suflicient to hold itpositively in its closed position against any pressure due tocompression of the mixture in the chamber 43. During the second strokeof the piston, since the valves 39 and 40 are both closed, sufficientsuction is produced in the chamber 17 to open the check valve 31, andair is taken into the chamber 17 and through the port 18 into the boreof cylinder 1 back of the piston 13, in sufiicient volume to fill thecylinder. At the same time, the stop-cock 36 is preferably open to ermitlubricating oil to flow into the pipe 34, so that it may be carried bythe fresh air into the cylinder and lubricate the piston 13 and the gate23. When the second stroke of the piston brings the packing bars 14 inline with the port-18, the cylinder is full of fresh air carryingwhatever oil may have been put into it during its intake. At thisinstant, at the beginning of the third stroke of the cycle underconsideration, the exhaust valve and the valve 39 is momentarily openedby its cam which at once fills the firing chamber 17 with fuel mixtureunder such compression fectively. The opening and closing of the valve39 is accomplished in the briefest interval possible to transfer themixture from the compartment 43 to the firing chamber 17, andimmediately upon the closing of the valve 39, and when the piston 13 is"in substantially the positionv in 'cated in Fig. 1,

that it Will. fire ef-i 'the mixture in the chamber 17 is fired by meansof the spark plug 29. This produces an operating pressure on the rearface of the piston 13 and also produces a pressure on the upper edge ofthe gate 23 holding it down against the rear face of the piston 13, sothat the pressure produced rotates the piston in the direction indicatedby the arrow. This action is continued until the packing bars 14 reachthe port 27, at which time the remaining pressure in the cylinder, isdissipated through the port 27 into the exhaust manifold 28 and sincethe next stroke (which is the first stroke of the next cycle ofoperation of the cylinder) draws in the next charge of fuel mixture andexhausts the burnt gases in the same manner above described, the exhaustvalve 26 remains open continuously for the type of cycle underconsideration, from the beginning of each third stroke until the end ofeach first stroke of successive cycles, to permit the exhaust of thecharge of cooling air from the cylinder, and to exhaust the burnt gasesas above described.

It will be noted that the front and rear faces-of the piston 13 arecurved so that they are convex, and that the curvature of the gate 23causes its lower edge to incline towards the shaft 10 proportionately tothe amount that the gate 23 projects into the bore of the cylinder.These curvatures co-operate to reduce to a minimum, the tendency thatwould otherwise exist to produce undue friction on the side of the gateadjacent the firing chamber in raising the gate into the slot 22. Withthe construction shown, the direction of the lifting pressure exerted onthe gate by the piston 13, is more nearly in line with the lower portionof the slot 22, than would be possible if the slot were straight insteadof curved.

Where my im roved engine consists of a larger number 0 cylinders thanthree cylinders, it will appear that various cycles of operation areavailable as desired, depending upon the number of piston rotationsemployed per cycle, and that the cam shaft gearing and the constructionand arrangement of the cams on the cam shaft may readily be proportionedto suit the requirements of any particular cycle of operation decidedupon. For example with a four cylinder arrangement, if there be but onefiringrotation per cycle there may be two rotations per cycle devoted tocooling each cylinder with fresh air, or if preferred, there may be onecooling rotation and two rotations devoted to compressing mixture in themixture chamber, and furthermore these several steps in the cycle may bearranged relatively to each other in any particular order desired.Itwill also appear her than four cylinders, for exam 1e six cylinders,that the cycle described or the three cylinder that in using a largernum engine may be employed in m each half of the engine and thatpreferably the firing strokes 1n any event should be equally spacedthroughout the cycle of oper- .one direction therefrom,

ation of the engine as a whole, and furthermore that for three or fourcylinders, the firing strokes in the several cylinders should be equallyspaced throughout the cycle.

By my construction, I provide am le cooling facilities for effectingpractica operation of the rotary engine under consideration and I alsoprovide efi'icient means for lubricating the internal parts of such aengine. Furthermore, the several parts of the engine are constructed anddisposed relatively to each other, so that the engines may beeconomically made and maintained.

While I have shown my invention in the particular embodiment abovedescribed, it will be understood that I do not limit myself to thisexact construction as I may employ equivalents known to the art at thetime of the filing of this application without departing from the scopeof the appended claims.

What I claim is:

1. In a rotary engine, the combination of a plurality of cylinders eachhaving substantially parallel end walls, a shaft extending throng saidcylinders coaxially with the bores thereof, a piston in each cylindercarried by said shaft and extending radially in each of said istonshaving a length substantially equa to the distance between the end wallsof the corresponding cylinder and being of substantially the same radiusas the bore of said cylinder,packing bars carried by each pistonengaging the bore of the corresponding cylinder, a firing chamber, foreach cylinder having a port opening into the latter, an exhaust valvefor each cylinder, a sliding gate resting upon the iston in eachcylinder be-- tween the port and exhaust valve thereof and separatingthe interior of said cylinder into two compartments, a compressedmixture passageway extending from each cylinder, a check valve in eachof said passageways permitting gas flow outwardly therein, a head forsaid cylinders havin a compressed mixture compartment thereincommunicating with said passageways, said head having also an intakepassageway therein for supplying fuel mixture to the engine, an intakevalve for each firing chamber for supplying fuel mixture from saidintake passageway to said firing chamber, a compressed mixture valve foreach firing chamber for supplying compressed fuel mixture from saidcompressed mixture compartment to said firing chamber, an air checkvalve for each firing chamber for admitting air thereto, each of saidair check valves having a spring holding said valve closed for suctionpressures of mixture intake, devices for supplying lubricating oil tothe air flowing through each of said air check valves, and cam mechanismactuated from said shaft and cyclically operating said intake valves,said compressed mixture valves and said exhaust valves and producing acycle of operation for each cylinder comprising intake, compression andfiring of fuel mixture and the Intake and exhaust of a cooling fresh airand lubricating charge, said cam mechanisms for the several cylindersbeing displaced angu larly from each other thereby spacing the firingstrokes of the several cylinders from each other.

2. In a rotary engine, the combination of a plurality of cylinders eachhaving substantially parallel end walls, a shaft extending through saidcylinders coaxially with the bores thereof, a piston in each cylindercarried hv said shaft and extending radially in one direction therefrom,each of said pistons having a length substantially equal to the distancebetween the end walls of the corresponding cylinder and being ofsubstantially the same radius as the bore of said cylinder, packing barscarried by each piston engag ing the bore of the corresponding cylinder,a firing chamber for each cylinder having a port opening into thelatter, an exhaust valve for each cylinder, a sliding gate resting uponthe piston in each cylinder between the port and exhaust valve thereofand separating the interior of said cylinder into two compartments, acompressed mixture passageway extending from each cylinder, a checkvalve in each of said passageways permitting gas flow outwardly therein,a head for said cylinders having a com pression-mixture compartmenttherein communicating with said passageways, said head having also anintake passageway therein for supplying fuel mixture to the engine, an'intake valve for each firing chamber for supplying fuel mixture fromsaid intake passageway to said firing chamber, a compressed mixturevalve for each firing chamber for supplying compressed fuel mixture fromsaid compressed mixture compartment to said firing cham her, an aircheck Vfl-lVG for each firing chamber for admitting air thereto, each ofsaid air check valves having a spring holding said valve closed forsuction pressures of mixture intake, and cam mechanism actuated fromsaid shaft and cyclically operating said intake valves, said compressedmixture valves and said exhaust valves and producing a cycle ofoperation for each cylinder comprising intake, compression and firing offuel mixture and the intake and exhaust. of a cooling fresh air charge,said cam mechanisms for the several cylinders being displaced angnlarlyfrom each other thereby spacing the firing strokes of the severalcylinders from each other.

3. In a rotary engine, the combination of a plurality of cylinders eachhaving substantially parallel end walls, a shaft extending supplyinglubricatin exhaust valve thereof and separating the inintakeand exhaustof a cooling fresh air through said cylinders coaxially with the firingchamber for each cylinder having a bores thereof, a piston in eachcylinder carport opening into the latter, an exhaust va ve ried by saidsha and extending radially in or each cyhnder, a sliding ate restingupon one direction therefrom, each of said pistons the piston in eachcylinder etween the port having a length substantially; equal to the andexhaust valve thereof and separating the distance between the end wa ofthe correinterior of said cylinder into two compartspondi-ng cylinderand being of substantially ments, a compressed mixture passageway exthesame radius as the bore of said cylinder, tending from each cylinder, acheck valve in packing bars carried by each piston engaging each of saidpassageways permitting gas flow the bore of the corresponding cylinder,a firoutwardly therein, a head for said cylinders ing chamber for eachcylinder having a port having a compressed mixture compartment openinginto the latter, an exhaust valve for therein' communicating with saidpassageeach cylinder, a sliding gate resting upon the ways, said headhaving also an intake paspiston in each cylinder between the port andsageway therein for supplying fuel mixture to the engine, an intakevalve for each firing chamber for supplying fuel mixture from saidintake passageway to said firing chamher, a compressed mixture valve foreach firing chamber for supplying compressed fuel mixture from saidcompressed mixture compartment to said firing chamber, an air checkvalve for each firing chamber for admitting air thereto, each of saidair check valves having a spring holding said valve closed for suctionpressures of mixture intake, devices terior of said cylinder into twocompartments, a compressed mixture passageway extending from eachcylinder, a check valve in each of said passageways permitting gas flowoutwardly therein, a head for said cylinders having a compressed mixturecompartment therein communicating with sai passageways, said head havingalso an intake passageway therein for supplying fuel mixture to theengine, an intake valve for each firing chamber for supplying fuelmixture from said in take passageway to said firing chamber, acompressed mixture valve for each firing chamber for supplyingcompressed fuel mixture from said compressed mixture compartment to saidfiring chamber, an air check valve for each firing chamber for admittingair thereto, each of said air check valves having a spring holding saidvalve closed for suction pressures of mixture intake, devices for oil tothe air flowing through each of sai air check valves, and cam mechanismactuated from said shaft and cyclically operating said intakevalvelslsaisdl cam mechanism actuated from said shaft and cyclicallyoperating said intake valves, said compressed mixture valves and saidexhaust valves.

5. In a rotary engine, the combination of a plurality of cylinders eachhaving subing through said cylinders coaxially with the bores thereof, aPlStOll'lIl each cylinder carried by said shaft and extending radiallyin one direction therefrom, each of said pistons having a lengthsubstantially equal to the distance between the end walls of thecorresponding cylinder and being of substantially the same radius as thebore of said cylinder, packing bars carried by each pistonengagcompressed mixture valves and said e valves and producing a cycleof o ration for each cylinder comprising mta e, com-. pression andfiring of el mixture and the firing chamber for each cylinder having aport opening into the latter, an exhaust valve for each cylinder, asliding gate resting upon the piston in each cylinder between the portand exhaust valve thereof and separating the and lubricating charge,said cam mechanisms for the several cylinders beingjdisplaced angularlyfrom each other there y spacing the firing strokes of the severalcylinders fromeach other, said cam mechanism for each cylindermomentarily opening the compressed mixture valve of said cylinderimmediately preceding its firingstroke.

4. In a rotary engine, the combination of a plurality of cylinders eachhaving substantially parallel end walls, a shaft extending through saidcylinders coaxially w1th the bores thereof, a piston in each cylindercarried by said shaft and extending radially 1n one direction therefrom,each of said pistons having a length substantially e ual to the distancebetween the end walls 0 the corresponding cylinder and being ofsubstantially the same radius 'as the bore of said cylinder, packingbars carried by each piston engaging the bore of the correspondlngcylinder, a

ments, a compressed mixture passageway extending from each cylinder, acheck valve in outwardly therein, a head for said cylinders having acompressed mixture compartment therein communicating with saidpassageways, said head having also an intake passageway therein forsupplying fuel mixture to the engine, an intake valve for each firingchamber for supplying fuel mixture from said intake passageway to said-firing chamber, a compressed mixture valve for each firing chamber forsupplying compressed fuel mixture from said compressed mixturecompartment to said firing chamber, an air check for supplyinglubricating oil to the air flowing through each of said air checkvalves, and

stantially parallel end walls, a shaft extend-,

ing the bore of the corresponding cylinder, :1

interior of said cylinder into two compart each of said passagewayspermitting gas flow a plurality of cylin valve for each firing chamberfor admitting air thereto, each of said air check valves having a springholding said valve closed for suction pressures of mixture intake, andcam mechanism actuated from said shaft and cyclically operating saidintake valves, said compressed mixture valves and said exhaust valves.

6. In a rotary engine, the combination of a plurality of cylinders eachhaving substantially parallel end walls, a shaft extending through saidcylinders coaxially with the bores thereof, a piston in each cylindercarried by said shaft and extending radially in one direction therefrom,each of said pistons having a length substantiall e ual to the distancebetween the end wal s o the corres )onding cylinder and being ofsubstantially the same radius as the bore of said cylinder,

acking bars carried by each iston engagmg the bore of the correspon ingcylinder, a firing chamber for each cylinder having a port opening intothe latter, an exhaust valve for each cylinder, a sliding gate restingupon the piston in each cylinder between the port and exhaust valvethereof and separating the interior of said cylinder into twocompartments, a compressed mixture compartment for storin compressedfuel mixture from each cylint er, an inlet passageway for supplying fuelmixture to each firing chamber, an intake valve for each firing chamberfor supplying fuel mixture from said intake passageway to said firingchamber, a com )ressed mixture valve for each firing chamber forsupplying compressed fuel mixture from said compressed mixture comartment to said firing chamber, anair chec valve for each firing chamberfor admitting air thereto, each of said air'check "alves having a springholding said valve closed for suction pressures of mixture intake,devices for supplying lubricating oil to the air flowing through each ofsaid air check valves, and cam mechanism actuated from said shaft andcyclically operating said intake valves, said compressed mixture valvesand said exhaust valves and producing a cycle of operation for eachcylinder com rising intake, compression and firing of uel mixture andthe intake and exhaust of a cooling fresh air and lubricating charge,said cam mechanisms for the several cylinders being displaced angularlyfrom each other thereby spacing the firin Y strokes of the severalcylinders from eacl other.

7. In a rotary en 'ne, the combination of ers each having substantiallyplarallel end walls, a shaft extending throng said cylinders coaxiallywith the bores thereof, a piston in each cylinder carried by said shaftand extending radially in one direction therefrom, each of said pistonshaving a length substantially equal to the distance between the endwalls of the corresponding. cylindcr and being of substantially the sameradius as the bore of said cylinder, packing bars carried by each istonengaging the bore of the corresponc ing cylinder, a firing chamber foreach cylinder having a port opening into the latter, an exhaust valvefor each cylinder, a sliding gate resting upon the )iston in eachcylinder between the port and exhaust valve thereof and separating theinterior of said cylinder into two compartments, a compressed mixturecompartment for storing compressed fuel mixture from each-cylinder, aninlet passageway for supplying fuel mixture to each firing chamber, anintake valve for each firing chamber for supplying fuel mixture fromsaid intake passageway to said firing chamber, a compressed mixturevalve for each firing chamber for supplying compressed fuel mixture fromsaid compressed mixture compartment to said firing chamber, an air checkvalve for each firing chamber for admitting air thereto, each of saidair check valves having a spring holding said valve closed for suctionpressures of mixture intake, and cam mechanism actuated from said shaftand cyclically operating said intake valves, said compressed mixturevalves and said exhaust valves and producing a cycle of operation foreach cylinder comprising intake, compression and firing of fuel mixtureand the intake and exhaust of a cooling fresh air charge, said cammechanisms for the several cylinders being displaced angularly from eachother thereby spacing the firing strokes of the several cylinders fromeach other.

8. In a rotary engine, the combination of a plurality ofcylinders eachhaving substantially arallel end walls, a shaft extending throng saidcylinders coaxially with the bores thereof, a iston in each cylindercarried by said sha t and extending radially in one directiontherefromeach of said pistons having a length substantially equal to the distancebetween the end walls of the corresponding cylinder and being ofsubstantially the same radius as the bore of said cylinder, packing barscarried by each piston engaging the bore of the corresponding cylinder,a firing chamber for each cylinder having a port opening into thelatter, an exhaust valvefor each cylinder, a slidin gate resting uponthe piston in each eylin er between a fuel mixture from ber, acompressed mixture valve'for each firmg chamber for supplying compressedfuel mixture from said compressed mixture compartment to said firingchamber, an air check valve for each firing chamber for admitting airthereto, each of said air check valves having a spring holding saidvalve closed for suction pressures of mixture intake, devices forsupplying lubricating oil to the air flowing through each of said aircheck valves, and cam mechanism actuated from said shaft and cyclicallyoperating said intake valves, said compressed mixture valves and saidexhaust valves and producing a cycle of operation for each cylindercomprising intake, compression and firing of fuel mixture and the intakeand exhaust of a cooling fresh air and lubricating charge, said cammechanism for the several cylinders being displaced angularly from eachother thereby spacing the firing strokes of the several cylinders fromeach other, said cam mechanism for each cylinder momentarily opening thecompressed mixture valve of said cylinder immediately preceding itsfiring stroke;

9. In a rotary engine, the combination of a plurality ofcylinders eachhaving substantially parallel end walls, a shaft extending through saidcylinders coaxially with the bores thereof, a piston in each cylindercarried by said shaft and extending radially in one direction therefrom,each of said pistons having a length substantiallyequal to the distancebetween the end walls of the cone sponding cylinderand being ofsubstantially t 1e same radius as packing bars carried by each pistonengagmg the bore of the corresponding cylinder, a firing chamber foreach cylinder havin a port opening into the latter, an exhaust va ve foreach cylinder, a sliding grate resting upon the piston in each cylindertween the port and exhaust valve thereof and separating the interior ofsaid cylinder into two compartments, a compressed mixture compartmentfor storing compressed fuel mixture from tially parallel end walls,

each cylinder, an inlet passa eway for supsupplying fuel mixture fromsaid intake passageway to said firing chamber, a compressed mixturevalve for each firing chamber for supplying compressed fuel mixture fromsaid compressed mixture compartment to said firin chamber, an air checkvalve for each firing chamber for admitting air thereto, each of saidair check valves having a spring holding said valve closed for suctionpresdevices for supplyeach of said air check valves, and cam mechanismactuated from said shaft and cyclically intake valves, said comoperatingsaid valves and said exhaust pressed mixture valves.

10. In a rotary engine, the combination of,

a plurality of cylinders eachhaving substana shaft extending mixturevalve for each the bore of said cylinder,

fuel mixture to each ring chamber, an intake valve for each firingchamber for through said cylinders coaxially with the bores thereof, aiston in each cylinder carried by said sha and extending radially in onedirection therefrom, each of said pistons having a length substantiallyequal to the'distance between the end walls of the correspondingcylinder and being of substantially the same radius as the bore of saidcylinder, packing bars carried by each piston engaging the bore of thecorresponding cylinder, a firing chamber for each cylinder having a portopening into the latter, an exhaust valve for each cylinder, a slidingate resting upon the piston in each cylinder etween the port and exhaustvalve thereof and separating the ments, a compressed mixture compartmenteach cylinder, an inlet passa eway for sup-- plying fuel mixture to eachring chamber, an intake valve for each firing chamber for supplying fuelmixture from said intake passageway to said firing chamber, a compressedfiring chamber for supplying compressed fuel mixture from saidcompressed mixture compartment to said firing chamber, an air checkvalve for each fir ing chamber for admitting air thereto, each of saidair check valves having a spring holding said valve closed for suctionpressures of mixture intake, and cam mechanism actuated from said shaftand cyclically operating said intake valves, said compressed mixturevalves and said exhaust valves.

11. In a rotary engine, the combination of a plurality of cylinders, apiston mounted for rotary movement in each of said cylinders, firingchambers for said cylinders, sliding gates separating said cylindersrespectively into two compartments, intake and exhaust valves for saidcylinders, a sprin restrained air-check valve for admitting resh air toeach cylinder when its intake valve is closed,

devices for supplying lubricatin oil to the air passing through saidcheck va ves, a compressed mixture compartment for storingcompressedfuel mixture from each cylinder, compressed mixture valves forsupplying said stored fuel mixture to said firing chambers, and cammechanism cyclically 0 ing said intake, exhaust and compress mixturevalves to include passing a fresh air cooling charge through eachcylinder for each cycle of operation of the engine.

12. In a rotar engine, the combination of 120 a plurality of cy inders,a piston mounted for rotary movement in each of said cylinders, firingchambers for said cylinders, sliding gates separating said cylindersrespectively into two compartments, valves for said cylinders, a springrestrained air. check valve for admitting fresh air to each cylinderwhen its-intake valve is closed, a compressed mixture compartment forstor I mg compressed fuel mixturefrom each cylinterior of said cylinderinto two comparteratintake and exhaust 2 inder, compressed mixturevalves for su plying said stored fuel mixture to said firing chambers,cam mechanism cyclically crating said intake, exhaust and cbmpressemixture valves to include passing a fresh air cooling charge througheach cylinder for each cycle of operation of the engine, said firing 0numbers opening through outer surfaces of said cylinders, and a commonhead closing said firing chambers and carrying said intake valves, saidcompressed-mixture valves and said compressed-mixture compartment.

13. In a rotary en ine, a cylinder block having a cylindrical ore andparallel and walls per )endicular to said bore, a piston mounted orrotation in said bore with a part of its lateral surface closelyadjacent said bore and shaped to leave a clearancespace for gasesbetween its remaining lateral surface and said bore, a gate engaging thelateral surface of said piston to separate said clearance space into twocompartments, an

intake valve for fuel mixture, an exhaust valve, an air inlet valveadmitting fresh air to said cylinder when said intake valve is closed,cam mechanism operatin said intake valve and said exhaust valve tolnclude passin a cooling charge of fresh air through said cy inder as apart of each of its cycles of oper- 3 ation, and devices for supplyinglubricating oil to the air passing through said air inlet valve.

14:. In a rotary en ine, a cylinder block having a cylindrical ore andparallel end a walls per endicular to said bore, a piston mounted orrotation in said bore with a part of its lateral surface closelyadjacent said bore and shaped to leave a clearance space for gasesbetween its remaining lateral surface and said bore, a gate engaging thelateral surface of said piston to separate said clearance space into twocompartments, an intake valve for fuel mixture, an exhaust valve, acompressed mixture compartment for receiving.

GOll'lpleSSed fuel mixture from said cylinder,

a compressed mixture valve, an air inlet valve admitting fresh air tosaid cylinder when said intake valve is closed, cam mechanism o cratingsaid intake valve, said comw' presse mixture valve, and said exhaustvalve to include passing a cooling charge of fresh air through saidcylinder as a part of each of its cycles of operation, a firing chamvberin said cylinder block communicating as with said cylinder here saidfirin chamber extending through said cylinder lock and having said airinlet valve opening into it and a head closin said firing chamber ancarryingv said inta e valve, said compressed so mixture valve, and saidcam mechanism, and

containing said compressed mixture compartment.

In witness whereof, I hereunto subscribe my name this 29th da ofOctober, A. D. 1928. G RHARDT PLATO.

